A U.S. Tank-Automotive and Armaments
Command study indicated that a combination
of technologies, specifically an asymmetrical
nickel supercapacitor combined with a low-cost, deep-cycle battery, was the optimum
power solution for military vehicles.
engine before the battery reaches a critically low state of charge. A drawback is
that such a system can seriously reduce
the life of standard lead-acid batteries,
given the number of times the battery
may be needed to restart the engine
during a 10-hour rest stop, for example.
In addition, the brief runtime allowed in
a no-idle area may allow for the battery
to be sufficiently recharged, which can
again shorten overall service life.
A relatively new form of energy storage — nickel supercapacitors (NC) —
is being seen as a viable alternative
in a variety of diesel engine applications, as have been demonstrated as
capable of delivering high power and
can be recharged quickly.
NCs with an asymmetrical, aque-
ous construction offer a number of
distinct differences and potential
advantages over conventional energy
storage technologies:
• As they are water-based, spills are
nontoxic and they will not catch
fire if exposed to open flame.
• NCs offer rapid charging capabil-
ity, typically within 20 to 30 sec-
onds after an engine start, with no
limit on charging rates.
• They do not cause catastrophic
failure under abusive conditions,
such as over-voltage, as the indi-
vidual cells are designed to vent,
meaning a failure in one cell will
not result in the failure of the entire
module. Under extreme conditions,
cells can be replenished if venting
for extended periods of time.
• They have no need for balanc-
ing electronics, and their simple,
robust design increases the time
for which the charge is retained.
•NCs can be recharged from
almost any energy source, even
the vehicle’s depleted battery.
NCs also offer advantages when
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